Many endoprostheses (or endoprosthetic devices), such as, for example, stent-grafts, are constructed to reinforce, replace, bridge, or otherwise treat a part of a blood vessel. An endoprosthesis may thus guide blood flow through a lumen defined by a generally tubular interior of such a vessel. Other tubular endoprostheses are designed for use in other body regions, for example, the esophagus, ureters, gastrointestinal tract and various ducts. In many cases, endoprostheses are constrained within a covering member or sheath, and when the covering member is removed, as during deployment, the devices expand, are expanded under force or self-expand to assume a larger diameter. From time to time, however, as a covering member is removed, the member may snag, catch, or become entangled on the endoprosthesis. Thus, improved endoprosthesis delivery systems are desirable.